tests/generic/030

#! /bin/bash
# FS QA Test No. generic/030
#
# Test mapped writes against remap+truncate down/up to ensure we get the data
# correctly written. This can expose data corruption bugs on filesystems where
# the block size is smaller than the page size.
#
#-----------------------------------------------------------------------
# Copyright (c) 2014 Red Hat, Inc.  All Rights Reserved.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
#-----------------------------------------------------------------------
#

seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"

here=`pwd`
tmp=/tmp/$$
status=1	# failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15

_cleanup()
{
    cd /
    rm -f $tmp.*
}

# get standard environment, filters and checks
. ./common/rc
. ./common/filter

# real QA test starts here

# Modify as appropriate.
_supported_fs generic
_supported_os Linux
_require_scratch
_require_xfs_io_command "mremap"

testfile=$SCRATCH_MNT/testfile

_scratch_mkfs > /dev/null 2>&1
_scratch_mount

# first case is just truncate down/truncate up to check that the mapped
# write after the truncate up is correctly handled.
$XFS_IO_PROG -t -f \
-c "truncate 5017k"             `# truncate     |       |` \
-c "pwrite -S 0x58 0 5017k"     `# write        |X...XXX|` \
-c "mmap -rw 0 5017k"           `# mmap         |       |` \
-c "truncate 5020k"             `# truncate up  |                        |` \
-c "mremap -m 5020k"            `# mremap up    |                        |` \
-c "mwrite -S 0x57 5017k 3k"    `# mwrite       |        WWWWWWWWWWWWWWWW|` \
-c "mremap 5017k "              `# mremap dn    |       |` \
-c "truncate 5017k"             `# mremap dn    |       |` \
-c "truncate 5020k"             `# truncate up  |                        |` \
-c "mremap -m 5020k"            `# mremap up    |                        |` \
-c "mwrite -S 0x59 5017k 3k"    `# mwrite       |        YYYYYYYYYYYYYYYY|` \
-c "close"      \
$testfile | _filter_xfs_io

echo "==== Pre-Remount ==="
hexdump -C $testfile
_scratch_cycle_mount
echo "==== Post-Remount =="
hexdump -C $testfile

rm -f $testfile
sync

# second case is to do a mwrite between the truncate to a block on the
# same page we are truncating within the EOF. This checks that a mapped
# write between truncate down and truncate up a further mapped
# write to the same page into the new space doesn't result in data being lost.
$XFS_IO_PROG -t -f \
-c "truncate 5017k"             `# truncate     |       |` \
-c "pwrite -S 0x58 0 5017k"     `# write        |X...XXX|` \
-c "mmap -rw 0 5017k"           `# mmap         |       |` \
-c "truncate 5020k"             `# truncate up  |                        |` \
-c "mremap -m 5020k"            `# mremap up    |                        |` \
-c "mwrite -S 0x57 5017k 3k"    `# mwrite       |        WWWWWWWWWWWWWWWW|` \
-c "mremap 5017k "              `# mremap dn    |       |` \
-c "truncate 5017k"             `# mremap dn    |       |` \
-c "mwrite -S 0x5a 5016k 1k"    `# mwrite       |    ZZZ                 |` \
-c "truncate 5020k"             `# truncate up  |                        |` \
-c "mremap -m 5020k"            `# mremap up    |                        |` \
-c "mwrite -S 0x59 5017k 3k"    `# mwrite       |        YYYYYYYYYYYYYYYY|` \
-c "close"      \
$testfile | _filter_xfs_io

echo "==== Pre-Remount ==="
hexdump -C $testfile
_scratch_cycle_mount
echo "==== Post-Remount =="
hexdump -C $testfile

# third case is the same as the first, but this time on unaligned byte
# boundaries rather than block boundaries. This mimics the exact mmap write
# patterns of the application that exposed the bug in the first place, and
# so is somewhat more complex and has repeated operations in it. 
$XFS_IO_PROG -t -f \
-c "truncate 5136912" \
-c "pwrite -S 0x58 0 5136912" \
-c "mmap -rw 0 5136912" \
-c "mremap 5136912" \
-c "truncate 5136912" \
-c "truncate 5139720" \
-c "mremap -m 5139720" \
-c "mwrite -S 0 5136912 2808" \
-c "mwrite -S 0 5136912 2808" \
-c "mwrite -S 0 5136912 2808" \
-c "mremap 5136912 " \
-c "truncate 5136912" \
-c "truncate 5139720" \
-c "mremap -m 5139720" \
-c "mwrite -S 0 5136912 2808" \
-c "mwrite -S 0 5136912 2808" \
-c "mwrite -S 0x59 5136912 2808" \
-c "truncate 5140480" \
-c "mremap 5140480" \
-c "msync -s 0 5140480" \
-c "mremap 5139720" \
-c "munmap" \
-c "close" \
$testfile | _filter_xfs_io

echo "==== Pre-Remount ==="
hexdump -C $testfile
_scratch_cycle_mount
echo "==== Post-Remount =="
hexdump -C $testfile

status=0
exit